Our miniature american eskie has a nasty habbit of nipping people on the calf and ankles when they are walking away. I am very carefull to keep her gated off from new people but sometimes when she is in the yard and someone enters she will get to them. She can be the most loving dog ever and she does not bother the chickens in or out of the run. She does not like some people and others she is totally fine with. I don't know how to stop her from doing this. Can anyone help?